Machine to Machine (M2M) communication is known as a form of data communication between devices that do not necessarily need human interaction and in general refers to telemetry. Using wireless mobile communications networks like a GSM/GPRS (Global System for Mobile Communication/General Packet Radio Service) or UMTS (Universal Mobile Telecommunication System) network enables a communication with mobile M2M devices and a cost-effective communication with localized devices, since expensive installation and maintenance of wired connections is not required.
Metering of power, gas, water and heating, monitoring of alarm systems, vending machines, medical devices and vital life functions, tracking and tracing of vehicles and road tolling are only a few examples in the very wide field of possible M2M applications. In recent years, the cost of access to public mobile data networks has been dropping while the capabilities of these networks continue to increase. The M2M device, software, network and service market is expected to grow rapidly worldwide in the next few years.
The wide-scale introduction of M2M devices in mobile networks will change network traffic profiles and traffic volumes and requires mobile network operators to rethink how to manage access to shared network resources. In contrast to various traditional mobile network services, where users expect an immediate access and response, for many M2M services immediacy is not a strong requirement. An effective access control is obviously relevant for non time critical M2M services that generate large volumes of network traffic but also for those M2M services that generate low traffic but have a large number of M2M devices deployed in the field.
Known access controls of M2M devices either permit an autonomous access to a mobile network for data exchange in a predetermined period or a specific time and date or use a centralized management of access, for example a server connected to the mobile network requesting data from the M2M devices.
Adversely a centralized management function that controls when an individual M2M device is allowed to exchange data does not scale well and necessitates additional signalling traffic towards every individual M2M device. Otherwise, when M2M devices autonomously decide on the moment in time at which to start exchanging data over a mobile network there is a risk that all devices start communicating simultaneously which may overload the network signalling or data channels.
The technical report 3GPP TR 22.868 proposes to instruct a group of M2M devices to transmit mobile network location updates at a specific date and time. A disadvantage of this approach is that the assumption is being made that the pattern of mobile network traffic load remains constant. This assumption may be true for M2M devices at a fixed geographic location, but not for mobile M2M devices as in this case mobile network traffic load patterns may vary with geographic location. Furthermore this approach does not considers that mobile network traffic load patterns may vary with time because of changes in local conditions, for example a music event or traffic jam may cause a peak load in mobile network traffic.